Theoretical and numerical studies of wave-packet propagation in tokamak plasmas

Details Theoretical and numerical studies of wave-packet propagation in tokamak plasmas Theoretical and numerical studies of wave-packet propagation in tokamak plasmas

2011-11-20

arxiv.org/abs/1111.4622v1

Physics

Plasma Physics

24 pages, 14 figures

Scientific paper

Theoretical and numerical studies of wave-packet propagation are presented to analyze the time varying 2D mode structures of electrostatic fluctuations in tokamak plasmas, using general flux coordinates. Instead of solving the 2D wave equations directly, the solution of the initial value problem is used to obtain the 2D mode structure, following the propagation of wave-packets generated by a source and reconstructing the time varying field. As application, the 2D WKB method is applied to investigate the shaping effects (elongation and triangularity) of tokamak geometry on the lower hybrid wave propagation and absorbtion. Meanwhile, the Mode Structure Decomposition (MSD) method is used to handle the boundary conditions and simplify the 2D problem to two nested 1D problems. The MSD method is related to that discussed earlier by Zonca and Chen [Phys. Fluids B 5, 3668 (1993)], and reduces to the well-known "ballooning formalism" [J. W. Connor, R. J. Hastie, and J. B. Taylor, Phys. Rev. Lett. 40, 396 (1978)], when spatial scale separation applies. This method is used to investigate the time varying 2D electrostatic ITG mode structure with a mixed WKB-full-wave technique. The time varying field pattern is reconstructed and the time asymptotic structure of the wave-packet propagation gives the 2D eigenmode and the corresponding eigenvalue. As a general approach to investigate 2D mode structures in tokamak plasmas, our method also applies for electromagnetic waves with general source/sink terms, either by an internal/external antenna or nonlinear wave interaction with zonal structures.

Affiliated with

Also associated with

No associations

Rating

Theoretical and numerical studies of wave-packet propagation in tokamak plasmas does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Theoretical and numerical studies of wave-packet propagation in tokamak plasmas, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Theoretical and numerical studies of wave-packet propagation in tokamak plasmas will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-130111